The Decline of Sharks Spells Trouble for Oceans

Ever since I was little, I knew I wanted to be a marine biologist who studied whales. To me, these were the most fascinating creatures that lived on our planet -- ones which no other species could rival.

And then, through my work at WWF leading our efforts to address the threat of bycatch to large marine animals from Canada's commercial fisheries, I got to dive -- and in one instance, quite literally -- into the fascinating world of sharks!

This incredible group of animals -- some 400 species globally -- have been around for hundreds of millions of years and, like whales, they have been persecuted by humans for centuries. While the vast majority of whaling has ceased, the perception of sharks being mindless killers combined with the increasing desire for their fins has meant that the take of sharks has actually increased in the last few decades. This has left many populations clinging to the edge of extinction.

And this means we have a serious problem.

This vast diversity of sharks globally play important roles in keeping our oceans healthy, all the way from bottom-feeding dogfish and nutrient-cycling basking sharks to top predators like Greenland and great white sharks. The decline of sharks spells trouble for the ocean. Removing key species like sharks, can have serious consequences for marine ecosystems, which, because they are connected to everything else, has repercussions for people everywhere.

In Canada, the main threat to sharks was direct capture and, but more recently -- and likely much more extensively -- bycatch in commercial fisheries. This is why WWF focuses on addressing the threat of bycatch and does this with the support of many others -- including those in industry, science and government. We do this to better understand the threats, find innovative solutions to reduce them, and ensure effective species protection and fisheries management policies are in place and, most importantly, implemented.

Lucky for me, in addition to encouraging people to develop better policies, I also find opportunities to work with shark in other ways. Last May, I was very fortunate to have an opportunity to meet the great whites who call South Africa home, face-to-face! Getting to cage dive with one of the supposed "most fearsome animals on the planet" was one of the most surreal and amazing experiences I've ever had. Instead of meeting a "monster" (which, by the way, I never expected them to be), I met animals who were peaceful and majestic. It made me realize that, like whales, I really couldn't imagine our world without them.

They've survived for so long, outlived many species including dinosaurs. Will we be the ones to wipe them out of existence? Not if I can help it.

A previous version of this blog misspelled the author's name. Her name is Tonya, not Tona.